Questions about Bullet Seating

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greatwhite

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I am quite new to reloading. I was preparing to reload for my 270 Winchester, I have deprimed and resized my cases.
I am now trying to determine how deep to seat the bullet. When I measure factory ammo with my calibers they are approx 3.28 inches but when I check my book it say I can be 3.54.

What gives and how deep should I seat the bullet?
 
Depends what type of tip and how you are measuring your bullets.

Also, the factory offerings are loaded to an industry standard as to chamber and function in all commercially made rifles for that particular chambering.The manuals may not necessarily reflect the number you measured as some different bullet styles will seat different than others.

If it is a hunting rifle just ensure your OAL fits your magazine and cycles properly then go ahead and do your load development.

Adjusting seating depth for performance is an area you can work into as your experience increases in reloading.
 
The book is only a starting suggestion.
You can start 5 thousands off the lands ,if you want.
And if your mag allows it.
You can take a firearm case,partially insert a bullet and chamber it.
Gently close the bolt and then gently eject.
This will give you the total COL ,for this specific bullet.
You can then use that as a reference.

Sometimes you made need to put a cut in the neck,using a dremel.

My 7mm rem ,Hornady calls for 3290 Col, my chamber allows 3490.
If I follow the book,that's a lot of jump..lol
 
Be careful about "chasing the lands" if you are a rookie. I presume this is a hunting rifle, so having a fair amount of bullet jump can save you grief in the field. The manufacturer of a specific bullet will give a recommended cartridge overall length, assuming the bullet doesnt already have a cannelure for that purpose. If you tell us the make and particulars of the bullet, I'm sure someone can dig up the number.
Once you become proficient at reloading you can look at "chasing the lands". FWIW - I have been reloading for several decades, and have set my bullet jump to .030 inch - this is for hunting applications. I dont consider bullet jump to be a prime variable for most hunting rifles - I've had rifles shoot extremely well with bullet jumps approaching 1/4 inch.
At this stage of the game, consistency from cartridge to cartridge should be the prime consideration.
 
You are loading a 270 Win, so most likely a hunting rifle? If so, first concern is that re-loads have to fit into the magazine - so measure inside magazine length - then deduct, say .100" to .150" for clearance - as you use the rifle, you may find you need more or can use less clearance - but fitting and feeding from magazine is where I start with a hunting rifle. Then I do the full length size to get easy slick chambering. Many topics that you read about "chasing lands", "shoulder bump" etc. have merit and are proven in bench rest and precise long range shooting - but that is not likely what you are shooting, just now. Those "higher end" fussy hand loading practices may or may not make a difference in your rifle. Most loading manuals show you how to confirm where you lands are - several techniques - to confirm that your magazine length is not actually "jamming" your bullets into the rifling as you chamber the round. - more to put your mind at ease at this stage...

So, fitting into the mag, and slick feeding is what you want now. And then every round going "bang" every time. Go through several hundred rounds like that - your shooting ability will improve - you may or may not want or need to try to improve the loading techniques that you had been using.
 
Yes I am loading for a Hunting Rifle a Parker Hale Midland 2100 to be exact.

Yes I did full a full length resize. I am using in this case Horandy 130 gr SP

Not sure how I can measure the inside of the mag since it is built in. Should I just then go with the same measurement that I get from my factory loads or maybe bump it up a bit or go right to what they say in my Lyman Manual?
 
greatwhite said:
Yes I am loading for a Hunting Rifle a Parker Hale Midland 2100 to be exact.

Yes I did full a full length resize. I am using in this case Horandy 130 gr SP

Not sure how I can measure the inside of the mag since it is built in. Should I just then go with the same measurement that I get from my factory loads or maybe bump it up a bit or go right to what they say in my Lyman Manual?
Click to expand...

Just load for the SAAMI spec for that bullet and you'll fit your magazine.
 
Hornady Il 130 grain is a short bullet that does not allow for a very high COL. 3.21 is what Hornady recommends. It works well in most cases. I would start there. Most likely your best COL will be between 3.18 and 3.25. This means not far from the cannelure. H4831 sc is the powder to use. Fed 210 has been the most accurate primer in my Sako 270.
 
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Yes I can do that, which the measurement I believe is 3.34 (I made a mistake at the top of the thread.), So I should try around there then. Curious why would the factory ammo be so much shorter I think I measured them at 3.28.

Kelly Timoffee said:
Just load for the SAAMI spec for that bullet and you'll fit your magazine.
Click to expand...
 
greatwhite said:
I am quite new to reloading. I was preparing to reload for my 270 Winchester, I have deprimed and resized my cases.
I am now trying to determine how deep to seat the bullet. When I measure factory ammo with my calibers they are approx 3.28 inches but when I check my book it say I can be 3.54.

What gives and how deep should I seat the bullet?
Click to expand...

If you have no mentor to physically show you how to reload for bullet depth, I suggest to follow the instructions of your reloading manual. From there you can creep-up towards the lands by .010" and then .005". Keep reloading simple: use the same bullet, primer and brass case, work around it with 3 different powders. Three shoot groups is all you require, for a hunting rifle that is, however, it's the very first shot that really counts. Good luck and have fun!
 
greatwhite said:
Yes I am loading for a Hunting Rifle a Parker Hale Midland 2100 to be exact.

Yes I did full a full length resize. I am using in this case Horandy 130 gr SP

Not sure how I can measure the inside of the mag since it is built in. Should I just then go with the same measurement that I get from my factory loads or maybe bump it up a bit or go right to what they say in my Lyman Manual?
Click to expand...

When I first started reloading in 1973 I also had a .270 and used Hornady bullets. Being a rookie I kept it simple, I seated the Hornady bullets to the cannelure.

It was a Remington 760 pump and the internet was not invented yet and the cannelure looked like a good spot to stop at. KISS - Keep it simple stupid

100G115G130G150G.jpg
 
greatwhite said:
Yes I can do that, which the measurement I believe is 3.34 (I made a mistake at the top of the thread.), So I should try around there then. Curious why would the factory ammo be so much shorter I think I measured them at 3.28.
Click to expand...

That amount of difference can just be in the tip difference, 0.006" isn't very much when measuring to the tip or for hunting ammo.The shorter bullet could actually be closer to the lands depending on the comparing of bullet profiles.Top photo of cartridge 3 and 4 show that very clearly.

Once you get more time loading and using different tools you will measure on the bullet jacket or ogive for doing comparisons, and that could just be where the factory decided to seat that bullet.
 
I will try after work today figuring out where the lands begin. I will take a case put a couple of cuts in it and put the bullet in just a bit and hopefully snug then I will chamber it and see how far it pushes it down.
 
Measure the length of your magazine and make a not of that in your log book. That is the max length you can load a round.

Seat a bullet in an empty, sized case, very , very long. Chamber it. If it won't chamber easily, don't force it. The bullet is hitting the rifling. The rifling will leave marks on the bullet. Seat the bullet deeper and deeper until it will chamber without touching the rifling. (Each quarter turn on the seater stem sets the bullet about 12 thou deeper.) Make a note of that length in your log book. That is the longest you can seat that make and weight of bullet. You have to make this measurement for each new bullet you want to try.

Once I know the OAL that just barely touches the rifling, I seat the bullet 20 thou deeper (assuming this OAL will fit the magazine). That puts the bullet 20 thou off the rifling and gets me good accuracy and no danger of the bullet engaging the rifling.

I have some rifles with deep freebores where the best OAL is too long to fit the magazine, so it is the mag that determines OAL.

The OAL mentioned in the book is not of much use, compared to making the simple measurement I have just explained.

The factory ammo is made short so it will fit in every rifle. The ammo companies and the rifle companies want to make sure everything is compatible, so all the feet are size 9 and all the boots are size 12. You can do better than that.
 
greatwhite said:
I will try after work today figuring out where the lands begin. I will take a case put a couple of cuts in it and put the bullet in just a bit and hopefully snug then I will chamber it and see how far it pushes it down.
Click to expand...

The trouble with this system (I have used it) is that the bullet may grab onto the chamber and pull out a bit when you extract. Oil the chamber and throat to reduce the risk. make multiple tries. If some measurements are identical, that is probably the correct one.
 
Ganderite said:
The trouble with this system (I have used it) is that the bullet may grab onto the chamber and pull out a bit when you extract. Oil the chamber and throat to reduce the risk. make multiple tries. If some measurements are identical, that is probably the correct one.
Click to expand...

To add to Ganderite's suggestion is another method as with his the only difference is I use a magic marker to show when the bullet touches, it's not always all the lands but when it removes the ink on the first point of contact is where I determine to be MY distance to lands, everybody is a bit different.
 
One of the ways of finding the lands has you paint up the bullet with a jiffy marker - as you close the bolt, if the bullet hits the lands, the case is pushed onto the bullet and scrapes off that jiffy marker - sometimes, when you open the bolt, only the case comes out - your bullet is "jammed" into the lands - use a cleaning rod through the muzzle to gently tap it out. You will see the scrape marks on the bullet that tell you where it was in the case as it jammed the lands.
Various magazine lengths come from different rifles - I think the Midland 2100 might have used a Mauser 98 magazine - I am not sure - you will find some that were 3.340" and some that were shorter - 3.2" (or maybe that was the pre-98 rifles?). The rounds have to fit the magazine, first.
Measuring the magazine length - disassemble the rifle? remove the floor plate? not certain what is needed on your rifle - even cut a length of dowel to specific length and try it. As mentioned above, if your bullets have a cannelure groove, pretty "safe" place to seat them to.
 
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